789 



above the girdled place dies (at least in European varieties), the part below 

 it is poorly nourished, so that the eyes remain sterile and should not be taken 

 into account in pruning. Besides this, girdled shoots break off very easily. 



In many trees also there is found frequently a hastening of the develop- 

 ment of the leaf buds below the place girdled, which can increase to the 

 formation of water sprouts. This case is more frequent in apple trees 

 than in pears. 



Recently, girdling has also been made use of in herbaceous plants with 

 edible fruits. Thus, for example, DanieF obtained larger fruit with the 

 Solaneae by this treatment. Other observers could not 

 confirm this, but found a retrogression in the develop- 

 ment of the whole plant". 



If we now pass over to the study of the anatomical 

 conditions produced by the girdling cut, or "pomological 

 magic ring," by means of the adjoining illustrations, we 

 shall, we believe, best further thereby an understanding 

 of the matter by giving first of all a general description 

 of 'Figs. 182 and 183. 



Fig. 182 represents a girdled grapevine; ii is the 

 lower overgrowth edge, it the upper edge ; bl, the bared 

 surface of the wood body. 



Fig. 183 is a longitudinal section through the lower, 

 smaller overgrowth edge (Fig. 182, u). S,S' is the plane 

 of the lower knife cut in girdling; S,S'C' is the protrud- 

 ing tissue of the overgrowth edge. H represents the 

 outermost layer of the exposed wood body; in this, g,g' 

 indicates the ducts and h,h' the porous wood cells. R, 

 as in Fig. 182, is the bark cut through in girdling, 

 which appears pushed back from the wood by the out- 

 swelling overgrowth tissue {r,C,C'). This tissue at s' 

 lies close against the wood and is protected externally 

 by a cork layer {k,k'). This protruding overgrowth 

 edge of parenchymatous tissue is differentiated by the 

 arched cambial zone c,c,c', into the parenchymatous 

 wound wood (wh) and the wound bark (wr). Both 

 are traversed by radiating medullary rays (m). 



Figs. 184 and 185 show how such an overgrowth edge appears in cross 

 section. The first was taken from the upper wound wall, close to the place 

 where it leaves the bark ; the second figure originates from a broader, most 

 distant region. 



In considering Fig. 183, we see that a mass of tissue has protruded 

 from the edge of the wound produced by a 3 to 4 fold division of the 



1 Daniel, Lucien, Effets de la decortication annulaire chez quelques plantes 

 herbacees. Conipt. rend. Paris 1900, p. 1253. 



2 Hedrick, Taylor and Welling-ton, Ringing herbaceous plants. New York State 

 Agric. Exp. Sta., Geneva, Bull. No. 2SS. 1906. 



Fig. 182. A ring- 

 ing wound on a 

 grapevine witli the 

 upper, more 

 strongly developed 

 overgrowth edge 

 (u') and the more 

 weakly formed 

 lower one (u). 



